Finishing petrolatum



, Feb. y1,7, 1942.

D. F. RENsHAw I FINISHING PETROLATUM Filed July 9, 1941 MIX/NQ (F1/MERS ART/v) Peo C555 ,MP/NH4 @fra/wv 70 A902555 PETROL/ITl/M INVENTOR vPatented Feb. 17, 1942 i c otiing the" simiiarfbia'ck, suspddmateral I k*are amenabletothisfsametreatment and forthe lpretrolatum .of vclean yellow vor bright greenv cast purposes 'of `this disclosure may beconsidered to "Whelolid, ,partili'larlylfrompetrmatuins which Y be equivalents. f

:ha been separated 'from stocksn t reviously '5 This petrolatum `startinglstocli 'is admixed with fw mreated.. 1, a process 'naphtha, `(a, straightrun naphtha` of f^'.,Pietrolatum products', asprepare Y ,y ,"Hal'e about-50`6`0fj ABLgravity, ,.initialboiling, point 'should be possessedmf a (clear,lightncolorbrilr 1(ASIM)"160,-2001F `nal boiling 4,point `(AS'IM)I `lliant`appearance,freedom:from,taste'jandio'dbr, 40G-140" FJ, ,usingAO- parts 'of the V.process andYstaltiilitylori"exposure,toflightaindainf-r Itfi() naphtha to, `60A-15,0 .'parts ofthepetrolatum-by 'has,iormerlylbeen,considerednecessary,'iriorder volume.The mixture issufli'cientlyl heatedx to tofatta'in these yprciperties',.f6.0 subject' thep'etlgolainsure solution; but a top,itemperature,,ofl 1,30??` E. v lturn torchemizcaltreatmnt is not eXc'eededto prevent adverse deterioration jricadput vfrequently y( of the'petrolatum. and other" reagrents.' ..,'Thi chemical After mixing, the, mixture, orsolutionis, placed frequently arriedoutuharithej .golatum nfij'settlins tank., fwheret Sf hld .all altem- "but` maybe"l and Y'frequently lis "accompli p'eraturefotabout lZQ' t 1 3 r'atgleas't: 72 treatmentotthe oilstock in which the" p I v, jhour's'., LDuring', thisperiod y,th re ysepar'ate's `out tum is contained yprior `to separation ofthe pet-l' from themixture a black sludge material, which rolatum therefrom. Of late, the use of solvent is separately drawn off and discarded, and the dewaxing methods in the industry to remove petsettling period must be at least surliciently long rolatum from long residuums or cylinder stocks to secure an optimum separation of this material. which have not been previously treated, as yby The settled solution is now pumped to a receivsulphuric acid, has given rise to raw petrolatum ing tank inthe filter house, where there is added stocks presenting some rather unusual problems to it Wash oils from previous ltrations of petin rening. l' rolatum solution. The addition of these Wash This invention has for its object the provi-` oils is customary at this point, is not great in 1 sion of a sequence of rening steps, not making amount, and 'has no influence upon the operause of chemical treatment, capable of producing tion of the process. The mixture, ready for la finished petrolatum of high brilliance, clear. tration, is usually about a 50-50 mixture of proclight color,.good taste, odor, and stability, and ess naphtha and petrolatum stock.

high electrical resistance fromstocks of the kinds Y The solution is then ltered by percolation for noted. y y 1 g A lv improvement of color, fullers earth, new or re- AIn order to more completely understand this vivied, usually revivilied, being an eflicient and invention, reference is now made rto the drawing usual filtration reagent. This filtration isk carattached hereto, which drawing shows inv dia- `ried out at about 150 F. .The ltration is so gram form the steps andsequence of steps in.- operated as to yield a filtered solution of bef volved. o y tween 150 and 25.0Lovibond color,\and the yield 'Ihe starting petrolatum, particularly when deligure for ,this operation is about 281/2 lifty galrived byA the benzol `ketone dewaxing of a resid- 40 lon barrels per ton of clay. The degree of ltraual parainic base crude stock may have the y tion in solution is not a ruling characteristic, following character. l since the color reduction duty may be shifted between these solution lters and straight stock Gravity DAPI "n". V32-34' lters later mentioned as desired, within reason- Flash F. (C. O. C.) -e 500-550 45 ablelmits l 210.. 90-110 V180. s' U' Y't@ AMP) 125 140 From the percolatlng solut1on lters the solu- Meltlng P0111 l; 75 1 tion is passed to and through a blotter press Penetratmn "f B1 *k* lilter wherein there is removed a tarry, gummy, Color y n vac carbonaceous material, the removal of Which at *Not onlyy is the material itseif black, but cpnsidembie" this point isessential to the process. colloid-like black material is carried 1n suspension.` After blotter ypressingJ the solution is reduced While, this iS typCal 0f the 11511211 Starting Det-` 4ina continuously operating pipe still to remove rolatum stock, `the material may be` heavier or overhead the process naphtha which is returned lighter, ranging from a soft to a hard stock, and` to the starting mixer, leaving as a bottoms areall such stocks, as well as oils from similar sources '55 duced petrolaturn.

' This reduced petrolatum is then percolated,

straight, through a filter to lfinal color. This final filtration is carried out at a temperature of 200 F. and-here any efficient filtration material may be used, a preference being had for bauxite.

When filtering to a finished color ofl 200-300 Lovibond, with bauxite, having previously filtered in solution as above, to 150-200 Lovibond, the yield figure is about 53 fifty ygallon barrels per ton. f

After final filtration, to produce petrolatums of various penetrations, some of the finished stocks may be blended with varying proportions of light neutral oils, as is usual in the art.

When finished, by the use of these stepsv and by the method outlined, the finished petrolatums when solid are brilliant, with a yellow cast for the lighter products and a reddish green cast for the darker series, as compared `with a dullish muddy appearance on petrolatums prepared by ordinary percolation filtration. Also, the materials so prepared are of superior ,electrical re- 1. That method for the finishing of 'petroiatum stocks to produce brilliant, clear petrolatums consisting of the Steps of diluting raw petrolatum stock with about an equal portion of process naphtha, subjecting the solution to a prolonged period V-of settling to settle and separate therefrom a sludge, passing the clarified solution through a percolating filtration with an adsorbent filter materiaLblotter pressingthe filtered solution, distilling the solution to remove naphtha therefrom, and percolating the reduced petrolatum through an adsorbent filter material to filter to'final color.

2. That method of finishing petrolatum stocks to produce brilliant, clear, petrolatums consisting of the following steps in sequence: diluting the petrolatum stock with solvent naphtha in about equal proportions, settling the solution for at least'about '72 hours to separate therefrom a sludge, passing the solution through an adsorptive filtration medium to lower the color thereof, passing the filtered solution through a blotter press to give a further clarification, distilling the solution to remove solvent naphtha therefrom, and passingthe reduced petrolatum through an vadsorptive filtration medium to bring it to final color.

3. The method of finishing petrolatum stocks to produce brilliant, clear, petrolatums consisting of the .following steps in sequence: diluting the petrolatum stock with solvent naphtha in about equal proportions, settling the solution for at least about '72 hours at 120 to 130 F., to sep- 'arate therefrom a sludge, passing the solution 

